C language: mathematical method of converting decimal system into binary system

First of all, we need to clarify the logic : How to convert decimal system to binary system

Our approach —— Short division

In decimal digits 10 For example

Our goal is to convert the decimal number into binary number

The pure mathematical method is as follows ：

10÷2=5 more than 0

5÷2=2 more than 1

2÷2=1 more than 0

1÷2=0 more than 1

Then write the remainder from bottom to top , namely 1010 You can get 10 Corresponding binary data

The specific code implementation is as follows ：

#include<stdio.h>
int main()
{
    int a,b,k,i;
    int remainder[30];
    while(1)
    {
        // Defined a remainder Array , Used to collect the remainder of short division , Stack output in reverse order .
        printf(" Please enter a decimal number :  ");
        scanf("%d",&a);
        k=0;
        while(a!=0)
        {
            b=a/2;
            k++;
            remainder[k]=a-b*2;
            a=a/2;
        };
        printf(" Converting to binary numbers is :  ");
        for (i=k; i>=1; i--)
        {
            printf("%d",remainder[i]);
        }
        printf("\n");
    }
    return 0;

Of course, there are simpler itoa Function to implement , But that's the application method , This article only introduces the basic mathematical method implementation